Update: Obama and Biden arrive in Washington
WASHINGTON -- Invoking hope and history, President-elect Barack Obama rolled into the capital city Saturday night pledging to help bring the nation "a new Declaration of Independence" and promising to rise to the stern challenges of the times. He kicked off a four-day inaugural celebration with a daylong rail trip, retracing the path Abraham Lincoln took in 1861.Obama began his day in Philadelphia, where he said the young nation had faced its "first true test" as a fragile democracy. He ended it in Washington, where his own tests await after his inauguration on Tuesday. (Watch video here)